por and para/ DE

Question 1

what do you use por for

Answer 1

unknown periods of time-
cause
rates (money)
type of communication - e.g phone, tablet etc

Question 2

what do you use para for

Answer 2

purpose
destinations
deadlines

Question 3

What are the uses of De?

Answer 3

Possession
Origin
Time
Cause
Material
Characteristics
Contents
Relationships
part of a whole - to express that one subject is part of another larger object.
A subject - to express a subject
A superlative -  to express a superlative comparison